1. Technical Field
The present invention relates to a liquid container for storing a liquid to be supplied to a liquid ejecting apparatus.
2. Related Art
In the related art, there is a liquid container for storing a liquid to be supplied to a liquid ejecting apparatus that uses a prism provided in a liquid container, as a means for detecting a residual amount of the liquid stored in the liquid container which falls below a predetermined amount. A portion of the prism protrudes into a liquid storage unit of the liquid container, and the other portion is exposed to an outer surface of the liquid container (for example, JP-A-2008-183909). In such a technology, light is incident onto the portion of the prism which is exposed from the outer surface of the liquid container, from an optical sensor provided at a printer side. When the portion of the prism which protrudes into the liquid storage unit is immersed in ink, the incident light is absorbed by the ink which comes into contact with the prism. Meanwhile, when the ink stored in the liquid storage unit is reduced and the portion of the prism protruding into the liquid storage unit is surrounded by air, the incident light is reflected by an end face of the prism, and thus is emitted in a direction of the optical sensor. Accordingly, the fact that the residual amount of the liquid stored in the liquid container falls below the predetermined amount, is detected based on the light quantity of the reflected light.
In addition, in the technology disclosed in JP-A-2008-183909, a carriage of the printer is also provided with a prism. The carriage and an ink cartridge are configured in such a way that the prism is covered by the ink cartridge when the ink cartridge is mounted on the carriage. When the ink cartridge is not mounted on the carriage, the light emitted from the optical sensor toward the prism is reflected from the end face of the prism, and thus is emitted in the direction of the optical sensor. When the ink cartridge is mounted on the carriage, the light emitted from the optical sensor toward the prism is absorbed by a wall surface of the ink cartridge.
As a result, in the technology disclosed in JP-A-2008-183909, as the carriage is moved to change the positions of the ink cartridge and the prism with respect to the optical sensor, it is possible to detect the residual amount of the ink and to determine whether or not the cartridge is mounted on the carriage, by using the same optical sensor.
However, in the above-described related art, it is necessary to provide the ink cartridge with a structure for covering the prism at the carriage side. This causes a ratio of the amount of ink, which can be stored in the ink cartridge, to the size of the ink cartridge to lessen. In addition, there are two positions, in which the carriage should be stopped with respect to the optical sensor, for detecting the mounting of the cartridge and the residual amount of the ink for one ink cartridge. Accordingly, it is necessary to accurately stop the carriage at 12 stop positions, for example, for a six-color printer. As a result, such a control is complicated. Such a problem is not limited to the printer, and is common in liquid ejecting apparatuses which supply the liquid from a detachable liquid container to eject the liquid.